The present invention relates to methods and systems for providing a secure e-mail messaging system using a vault server in conjunction with a client-side restricted-execution vault-mail environment.
The advent of e-mail has greatly expanded and enhanced traditional communication channels. The ability to attach documents to e-mail messages has provided users an easy way to share information. However, with the ubiquitous use of e-mail communication, there has been an increasing concern over the security of such information. Besides the lack of control over second-hand distribution, e-mail content and attachments may be accessed by unauthorized individuals who are familiar with various methods of “hacking” into so-called “secure” information systems and gateways.
In the prior art, solutions exist for solving the authenticity and integrity issues in the email protocol (e.g. S/MIME, SMTPS, and PGP). These solutions are often difficult to implement as they require advanced configuration from the users. In addition, these solutions do not solve the issue of controlling content distribution.
Other solutions exist for ensuring that files cannot be opened by unauthorized users. Enterprise digital rights-management (DRM) systems, such as Microsoft's Office Information Rights Management package, can restrict specific type of documents from being opened by unauthorized individuals. Enterprise DRM systems typically require protected files to be changed, limiting system support to select file types and versions.
Other secure-messaging solutions employ a similar approach, also referred to as a “vault” in the industry. As a prior-art example, McNulty, in US Patent Publication No. 20070011259 (hereinafter referred to as McNulty '259), discloses a secure messaging and data transaction system and method. However, in McNulty '259, a protected message is rendered (i.e. displayed) on the vault server itself, which means that the message's external presentation needs to be converted into a web format. This prevents the use of typical desktop applications for accessing such a message. Furthermore, the message's recipient can copy (e.g. “cut and paste”), print, and/or save the message's content at will. The Secure Vault from Secure Data in Motion, Inc., dba Sigaba, San Mateo, Calif., provides a similar solution to McNulty '259.
Joshi et al., in US Patent Publication No. 20050149726 (hereinafter referred to as Joshi '726) discloses systems and methods for secure client applications. Joshi '726 describes the use of a restricted execution environment to handle files (e.g. e-mail attachments) received from an external source. However, the disclosure of Joshi '726 is aimed at protecting the client (i.e. the recipient) and, as such, does not provide the sender with any protection (e.g. by preventing the client from copying or forwarding the message). Huddleston, in US Patent Publication No. 20050273856 (hereinafter referred to as Huddleston '856), discloses a method and system for isolating suspicious email using a similar approach.
Leonard et al. in U.S. Pat. No. 6,721,784 (hereinafter referred to as Leonard '784), teaches a system and method for enabling the originator of an electronic mail message to preset an expiration time, date, and/or event, and to control and track processing or handling by all recipients. However, the invention of Leonard '784 requires a special “viewer” application to run on the recipient's computer, which restricts the types of files that can be sent to a few well-known types.
It would be desirable to have methods and systems for providing a secure e-mail messaging system using a vault server in conjunction with a client-side restricted-execution vault-mail environment. Such methods would, inter alia, overcome the limitations of the prior art as described above.